This invention relates to an amphibian vehicle, and more particularly to an amphibian vehicle capable of running in an unfrozen water area, an icy water area, or a muddy area by means of floaters, each of which consists of a cylindrical body having buoyancy and provided with helical blades on the outer circumferential surface thereof.
The moving units employed in conventional amphibian vehicles are mainly a crawler type moving unit using endless tracks and a combination moving unit in which a vehicle and propellers are united with one another. However, an amphibian vehicle employing the former moving unit has an extremely low running performance, and an amphibian vehicle employing the latter moving unit has great difficulties in running in a sludgy and muddy area.
On the other hand, the development of resources in cold sea areas including the development of oil fields in the North Sea areas has been carried out actively in recent years. An amphibian vehicle running in a cold sea area, especially, a frozen sea area must be able to run freely in a sea area with no ice (an unfrozen sea area), a sea area with comparatively small blocks of ice in great concentrations (a broken ice sea area), and a sea area covered with ice which is thick enough to bear the weight of the amphibian vehicle (a thick-ice-covered sea area). Also, such an amphibian vehicle must be able to break comparatively thin ice continuously, run from an unfrozen or a broken ice sea area onto an ice surface, and travel from an on-ice area into an unfrozen or a broken-ice sea area. Since an amphibian vehicle runs in a frozen sea area in various manners as mentioned above, it must also have excellent stability and maneuverability.